Message ID | 20240412165230.2009746-1-jrife@google.com |
---|---|
Headers | show |
Series | selftests/bpf: Add sockaddr tests for kernel networking | expand |
> It would be better to check if args->msglen > sizeof(arg->msg) although > this function is just for test cases. Same for args->addr.addrlen. Ack. I will add this. Thanks, Jordan On Fri, Apr 12, 2024 at 6:26 PM Kui-Feng Lee <sinquersw@gmail.com> wrote: > > > > On 4/12/24 09:52, Jordan Rife wrote: > > This patch adds a set of kfuncs to bpf_testmod that can be used to > > manipulate a socket from kernel space. > > > > Signed-off-by: Jordan Rife <jrife@google.com> > > --- > > .../selftests/bpf/bpf_testmod/bpf_testmod.c | 139 ++++++++++++++++++ > > .../bpf/bpf_testmod/bpf_testmod_kfunc.h | 27 ++++ > > 2 files changed, 166 insertions(+) > > > > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > > index 39ad96a18123f..663df8148097e 100644 > > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > > @@ -10,18 +10,29 @@ > > #include <linux/percpu-defs.h> > > #include <linux/sysfs.h> > > #include <linux/tracepoint.h> > > +#include <linux/net.h> > > +#include <linux/socket.h> > > +#include <linux/nsproxy.h> > > +#include <linux/inet.h> > > +#include <linux/in.h> > > +#include <linux/in6.h> > > +#include <linux/un.h> > > +#include <net/sock.h> > > #include "bpf_testmod.h" > > #include "bpf_testmod_kfunc.h" > > > > #define CREATE_TRACE_POINTS > > #include "bpf_testmod-events.h" > > > > +#define CONNECT_TIMEOUT_SEC 1 > > + > > typedef int (*func_proto_typedef)(long); > > typedef int (*func_proto_typedef_nested1)(func_proto_typedef); > > typedef int (*func_proto_typedef_nested2)(func_proto_typedef_nested1); > > > > DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123; > > long bpf_testmod_test_struct_arg_result; > > +static struct socket *sock; > > > > struct bpf_testmod_struct_arg_1 { > > int a; > > @@ -494,6 +505,124 @@ __bpf_kfunc static u32 bpf_kfunc_call_test_static_unused_arg(u32 arg, u32 unused > > return arg; > > } > > > > +__bpf_kfunc int bpf_kfunc_init_sock(struct init_sock_args *args) > > +{ > > + int proto; > > + > > + if (sock) > > + pr_warn("%s called without releasing old sock", __func__); > > + > > + switch (args->af) { > > + case AF_INET: > > + case AF_INET6: > > + proto = args->type == SOCK_STREAM ? IPPROTO_TCP : IPPROTO_UDP; > > + break; > > + case AF_UNIX: > > + proto = PF_UNIX; > > + break; > > + default: > > + pr_err("invalid address family %d\n", args->af); > > + return -EINVAL; > > + } > > + > > + return sock_create_kern(&init_net, args->af, args->type, proto, &sock); > > +} > > + > > +__bpf_kfunc void bpf_kfunc_close_sock(void) > > +{ > > + if (sock) { > > + sock_release(sock); > > + sock = NULL; > > + } > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_kernel_connect(struct addr_args *args) > > +{ > > + /* Set timeout for call to kernel_connect() to prevent it from hanging, > > + * and consider the connection attempt failed if it returns > > + * -EINPROGRESS. > > + */ > > + sock->sk->sk_sndtimeo = CONNECT_TIMEOUT_SEC * HZ; > > + > > + return kernel_connect(sock, (struct sockaddr *)&args->addr, > > + args->addrlen, 0); > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_kernel_bind(struct addr_args *args) > > +{ > > + return kernel_bind(sock, (struct sockaddr *)&args->addr, args->addrlen); > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_kernel_listen(void) > > +{ > > + return kernel_listen(sock, 128); > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args) > > +{ > > + struct msghdr msg = { > > + .msg_name = &args->addr.addr, > > + .msg_namelen = args->addr.addrlen, > > + }; > > + struct kvec iov; > > + int err; > > + > > + iov.iov_base = args->msg; > > + iov.iov_len = args->msglen; > > It would be better to check if args->msglen > sizeof(arg->msg) although > this function is just for test cases. Same for args->addr.addrlen. > > > + > > + err = kernel_sendmsg(sock, &msg, &iov, 1, args->msglen); > > + args->addr.addrlen = msg.msg_namelen; > > + > > + return err; > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args) > > +{ > > + struct msghdr msg = { > > + .msg_name = &args->addr.addr, > > + .msg_namelen = args->addr.addrlen, > > + }; > > + struct kvec iov; > > + int err; > > + > > + iov.iov_base = args->msg; > > + iov.iov_len = args->msglen; > > + > > + iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &iov, 1, args->msglen); > > + err = sock_sendmsg(sock, &msg); > > + args->addr.addrlen = msg.msg_namelen; > > + > > + return err; > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_kernel_getsockname(struct addr_args *args) > > +{ > > + int err; > > + > > + err = kernel_getsockname(sock, (struct sockaddr *)&args->addr); > > + if (err < 0) > > + goto out; > > + > > + args->addrlen = err; > > + err = 0; > > +out: > > + return err; > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_kernel_getpeername(struct addr_args *args) > > +{ > > + int err; > > + > > + err = kernel_getpeername(sock, (struct sockaddr *)&args->addr); > > + if (err < 0) > > + goto out; > > + > > + args->addrlen = err; > > + err = 0; > > +out: > > + return err; > > +} > > + > > BTF_KFUNCS_START(bpf_testmod_check_kfunc_ids) > > BTF_ID_FLAGS(func, bpf_testmod_test_mod_kfunc) > > BTF_ID_FLAGS(func, bpf_kfunc_call_test1) > > @@ -520,6 +649,15 @@ BTF_ID_FLAGS(func, bpf_kfunc_call_test_ref, KF_TRUSTED_ARGS | KF_RCU) > > BTF_ID_FLAGS(func, bpf_kfunc_call_test_destructive, KF_DESTRUCTIVE) > > BTF_ID_FLAGS(func, bpf_kfunc_call_test_static_unused_arg) > > BTF_ID_FLAGS(func, bpf_kfunc_call_test_offset) > > +BTF_ID_FLAGS(func, bpf_kfunc_init_sock) > > +BTF_ID_FLAGS(func, bpf_kfunc_close_sock) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_connect) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_bind) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_listen) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_sendmsg) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_sock_sendmsg) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getsockname) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getpeername) > > BTF_KFUNCS_END(bpf_testmod_check_kfunc_ids) > > > > static int bpf_testmod_ops_init(struct btf *btf) > > @@ -650,6 +788,7 @@ static int bpf_testmod_init(void) > > return ret; > > if (bpf_fentry_test1(0) < 0) > > return -EINVAL; > > + sock = NULL; > > return sysfs_create_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file); > > } > > > > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h > > index 7c664dd610597..cdf7769a7d8ca 100644 > > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h > > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h > > @@ -64,6 +64,22 @@ struct prog_test_fail3 { > > char arr2[]; > > }; > > > > +struct init_sock_args { > > + int af; > > + int type; > > +}; > > + > > +struct addr_args { > > + char addr[sizeof(struct __kernel_sockaddr_storage)]; > > + int addrlen; > > +}; > > + > > +struct sendmsg_args { > > + struct addr_args addr; > > + char msg[10]; > > + int msglen; > > +}; > > + > > struct prog_test_ref_kfunc * > > bpf_kfunc_call_test_acquire(unsigned long *scalar_ptr) __ksym; > > void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym; > > @@ -106,4 +122,15 @@ void bpf_kfunc_call_test_fail3(struct prog_test_fail3 *p); > > void bpf_kfunc_call_test_mem_len_fail1(void *mem, int len); > > > > void bpf_kfunc_common_test(void) __ksym; > > + > > +int bpf_kfunc_init_sock(struct init_sock_args *args) __ksym; > > +void bpf_kfunc_close_sock(void) __ksym; > > +int bpf_kfunc_call_kernel_connect(struct addr_args *args) __ksym; > > +int bpf_kfunc_call_kernel_bind(struct addr_args *args) __ksym; > > +int bpf_kfunc_call_kernel_listen(void) __ksym; > > +int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args) __ksym; > > +int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args) __ksym; > > +int bpf_kfunc_call_kernel_getsockname(struct addr_args *args) __ksym; > > +int bpf_kfunc_call_kernel_getpeername(struct addr_args *args) __ksym; > > + > > #endif /* _BPF_TESTMOD_KFUNC_H */
Martin, Thank you for the detailed feedback. > Can a separate global lock/mutex (not the lock_sock) be acquired first before > using the sock pointer in the kfuncs? Sure. I will add the mutex around the socket operations. As for the single global sock pointer, I wanted to keep it simple in this patch series to fulfill the current use case. I agree it might be overkill for now to add the bpf map and such. > Is it better to set sk_sndtimeo in bpf_kfunc_init_sock() ? > All these new kfunc should have the KF_SLEEPABLE flag. > bpf_testmod_exit() should probably do this NULL check and sock_release() also. Ack. I will add this. > nit. Can "struct sockaddr_storage addr;" be directly used instead of a char array? When using "struct sockaddr_storage addr;" directly, the BPF program fails to load with the following error message. > libbpf: prog 'kernel_connect': BPF program load failed: Invalid argument > libbpf: prog 'kernel_connect': -- BEGIN PROG LOAD LOG -- > 0: R1=ctx() R10=fp0 > ; return bpf_kfunc_call_kernel_connect(args); @ sock_addr_kern.c:26 > 0: (85) call bpf_kfunc_call_kernel_connect#99994 > arg#0 pointer type STRUCT addr_args must point to scalar, or struct with scalar > processed 1 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 > -- END PROG LOAD LOG -- > libbpf: prog 'kernel_connect': failed to load: -22 > libbpf: failed to load object 'sock_addr_kern' > libbpf: failed to load BPF skeleton 'sock_addr_kern': -22 > load_sock_addr_kern:FAIL:skel unexpected error: -22 > test_sock_addr:FAIL:load_sock_addr_kern unexpected error: -1 (errno 22) > #288 sock_addr:FAIL -Jordan On Tue, Apr 16, 2024 at 2:43 AM Martin KaFai Lau <martin.lau@linux.dev> wrote: > > On 4/12/24 9:52 AM, Jordan Rife wrote: > > This patch adds a set of kfuncs to bpf_testmod that can be used to > > manipulate a socket from kernel space. > > > > Signed-off-by: Jordan Rife <jrife@google.com> > > --- > > .../selftests/bpf/bpf_testmod/bpf_testmod.c | 139 ++++++++++++++++++ > > .../bpf/bpf_testmod/bpf_testmod_kfunc.h | 27 ++++ > > 2 files changed, 166 insertions(+) > > > > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > > index 39ad96a18123f..663df8148097e 100644 > > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > > @@ -10,18 +10,29 @@ > > #include <linux/percpu-defs.h> > > #include <linux/sysfs.h> > > #include <linux/tracepoint.h> > > +#include <linux/net.h> > > +#include <linux/socket.h> > > +#include <linux/nsproxy.h> > > +#include <linux/inet.h> > > +#include <linux/in.h> > > +#include <linux/in6.h> > > +#include <linux/un.h> > > +#include <net/sock.h> > > #include "bpf_testmod.h" > > #include "bpf_testmod_kfunc.h" > > > > #define CREATE_TRACE_POINTS > > #include "bpf_testmod-events.h" > > > > +#define CONNECT_TIMEOUT_SEC 1 > > + > > typedef int (*func_proto_typedef)(long); > > typedef int (*func_proto_typedef_nested1)(func_proto_typedef); > > typedef int (*func_proto_typedef_nested2)(func_proto_typedef_nested1); > > > > DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123; > > long bpf_testmod_test_struct_arg_result; > > +static struct socket *sock; > > > > struct bpf_testmod_struct_arg_1 { > > int a; > > @@ -494,6 +505,124 @@ __bpf_kfunc static u32 bpf_kfunc_call_test_static_unused_arg(u32 arg, u32 unused > > return arg; > > } > > > > +__bpf_kfunc int bpf_kfunc_init_sock(struct init_sock_args *args) > > +{ > > + int proto; > > + > > + if (sock) > > + pr_warn("%s called without releasing old sock", __func__); > > hmm...this global sock pointer is quite unease. e.g. what if multiple tasks > trying to use init/close/connect... in parallel. > > Storing sock in a bpf map will be better but that may be overkill for testing. > Can a separate global lock/mutex (not the lock_sock) be acquired first before > using the sock pointer in the kfuncs? > > > + > > + switch (args->af) { > > + case AF_INET: > > + case AF_INET6: > > + proto = args->type == SOCK_STREAM ? IPPROTO_TCP : IPPROTO_UDP; > > + break; > > + case AF_UNIX: > > + proto = PF_UNIX; > > + break; > > + default: > > + pr_err("invalid address family %d\n", args->af); > > + return -EINVAL; > > + } > > + > > + return sock_create_kern(&init_net, args->af, args->type, proto, &sock); > > +} > > + > > +__bpf_kfunc void bpf_kfunc_close_sock(void) > > +{ > > + if (sock) { > > + sock_release(sock); > > bpf_testmod_exit() should probably do this NULL check and sock_release() also. > > > + sock = NULL; > > + } > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_kernel_connect(struct addr_args *args) > > +{ > > + /* Set timeout for call to kernel_connect() to prevent it from hanging, > > + * and consider the connection attempt failed if it returns > > + * -EINPROGRESS. > > + */ > > + sock->sk->sk_sndtimeo = CONNECT_TIMEOUT_SEC * HZ; > > Is it better to set sk_sndtimeo in bpf_kfunc_init_sock() ? > > > + > > + return kernel_connect(sock, (struct sockaddr *)&args->addr, > > + args->addrlen, 0); > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_kernel_bind(struct addr_args *args) > > +{ > > + return kernel_bind(sock, (struct sockaddr *)&args->addr, args->addrlen); > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_kernel_listen(void) > > +{ > > + return kernel_listen(sock, 128); > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args) > > +{ > > + struct msghdr msg = { > > + .msg_name = &args->addr.addr, > > + .msg_namelen = args->addr.addrlen, > > + }; > > + struct kvec iov; > > + int err; > > + > > + iov.iov_base = args->msg; > > + iov.iov_len = args->msglen; > > + > > + err = kernel_sendmsg(sock, &msg, &iov, 1, args->msglen); > > + args->addr.addrlen = msg.msg_namelen; > > + > > + return err; > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args) > > +{ > > + struct msghdr msg = { > > + .msg_name = &args->addr.addr, > > + .msg_namelen = args->addr.addrlen, > > + }; > > + struct kvec iov; > > + int err; > > + > > + iov.iov_base = args->msg; > > + iov.iov_len = args->msglen; > > + > > + iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &iov, 1, args->msglen); > > + err = sock_sendmsg(sock, &msg); > > + args->addr.addrlen = msg.msg_namelen; > > + > > + return err; > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_kernel_getsockname(struct addr_args *args) > > +{ > > + int err; > > + > > + err = kernel_getsockname(sock, (struct sockaddr *)&args->addr); > > + if (err < 0) > > + goto out; > > + > > + args->addrlen = err; > > + err = 0; > > +out: > > + return err; > > +} > > + > > +__bpf_kfunc int bpf_kfunc_call_kernel_getpeername(struct addr_args *args) > > +{ > > + int err; > > + > > + err = kernel_getpeername(sock, (struct sockaddr *)&args->addr); > > + if (err < 0) > > + goto out; > > + > > + args->addrlen = err; > > + err = 0; > > +out: > > + return err; > > +} > > + > > BTF_KFUNCS_START(bpf_testmod_check_kfunc_ids) > > BTF_ID_FLAGS(func, bpf_testmod_test_mod_kfunc) > > BTF_ID_FLAGS(func, bpf_kfunc_call_test1) > > @@ -520,6 +649,15 @@ BTF_ID_FLAGS(func, bpf_kfunc_call_test_ref, KF_TRUSTED_ARGS | KF_RCU) > > BTF_ID_FLAGS(func, bpf_kfunc_call_test_destructive, KF_DESTRUCTIVE) > > BTF_ID_FLAGS(func, bpf_kfunc_call_test_static_unused_arg) > > BTF_ID_FLAGS(func, bpf_kfunc_call_test_offset) > > +BTF_ID_FLAGS(func, bpf_kfunc_init_sock) > > +BTF_ID_FLAGS(func, bpf_kfunc_close_sock) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_connect) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_bind) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_listen) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_sendmsg) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_sock_sendmsg) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getsockname) > > +BTF_ID_FLAGS(func, bpf_kfunc_call_kernel_getpeername) > > All these new kfunc should have the KF_SLEEPABLE flag. > > > BTF_KFUNCS_END(bpf_testmod_check_kfunc_ids) > > > > static int bpf_testmod_ops_init(struct btf *btf) > > @@ -650,6 +788,7 @@ static int bpf_testmod_init(void) > > return ret; > > if (bpf_fentry_test1(0) < 0) > > return -EINVAL; > > + sock = NULL; > > return sysfs_create_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file); > > } > > > > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h > > index 7c664dd610597..cdf7769a7d8ca 100644 > > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h > > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod_kfunc.h > > @@ -64,6 +64,22 @@ struct prog_test_fail3 { > > char arr2[]; > > }; > > > > +struct init_sock_args { > > + int af; > > + int type; > > +}; > > + > > +struct addr_args { > > + char addr[sizeof(struct __kernel_sockaddr_storage)]; > > nit. Can "struct sockaddr_storage addr;" be directly used instead of a char array? > > > + int addrlen; > > +}; > > + > > +struct sendmsg_args { > > + struct addr_args addr; > > + char msg[10]; > > + int msglen; > > +}; > > + > > struct prog_test_ref_kfunc * > > bpf_kfunc_call_test_acquire(unsigned long *scalar_ptr) __ksym; > > void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym; > > @@ -106,4 +122,15 @@ void bpf_kfunc_call_test_fail3(struct prog_test_fail3 *p); > > void bpf_kfunc_call_test_mem_len_fail1(void *mem, int len); > > > > void bpf_kfunc_common_test(void) __ksym; > > + > > +int bpf_kfunc_init_sock(struct init_sock_args *args) __ksym; > > +void bpf_kfunc_close_sock(void) __ksym; > > +int bpf_kfunc_call_kernel_connect(struct addr_args *args) __ksym; > > +int bpf_kfunc_call_kernel_bind(struct addr_args *args) __ksym; > > +int bpf_kfunc_call_kernel_listen(void) __ksym; > > +int bpf_kfunc_call_kernel_sendmsg(struct sendmsg_args *args) __ksym; > > +int bpf_kfunc_call_sock_sendmsg(struct sendmsg_args *args) __ksym; > > +int bpf_kfunc_call_kernel_getsockname(struct addr_args *args) __ksym; > > +int bpf_kfunc_call_kernel_getpeername(struct addr_args *args) __ksym; > > + > > #endif /* _BPF_TESTMOD_KFUNC_H */ >
On 4/17/24 09:59, Jordan Rife wrote: >> nit. Can "struct sockaddr_storage addr;" be directly used instead of a char array? > When using "struct sockaddr_storage addr;" directly, the BPF program > fails to load with the following error message. > >> libbpf: prog 'kernel_connect': BPF program load failed: Invalid argument >> libbpf: prog 'kernel_connect': -- BEGIN PROG LOAD LOG -- >> 0: R1=ctx() R10=fp0 >> ; return bpf_kfunc_call_kernel_connect(args); @ sock_addr_kern.c:26 >> 0: (85) call bpf_kfunc_call_kernel_connect#99994 >> arg#0 pointer type STRUCT addr_args must point to scalar, or struct with scalar >> processed 1 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 >> -- END PROG LOAD LOG -- >> libbpf: prog 'kernel_connect': failed to load: -22 >> libbpf: failed to load object 'sock_addr_kern' >> libbpf: failed to load BPF skeleton 'sock_addr_kern': -22 >> load_sock_addr_kern:FAIL:skel unexpected error: -22 >> test_sock_addr:FAIL:load_sock_addr_kern unexpected error: -1 (errno 22) >> #288 sock_addr:FAIL I just looked into the definition of struct __kernel_sockaddr_sotrage and the change log of this type. It has a pointer in it, causing this error. According to the commit log, the pointer is there to fix an alignment issue. I am curious if we can replace the pointer with intptr_t to fix this error. Of course, this should not block this patch set.